Mining-drill thread-box and support.



G. W. NIXON. MINING DRILL THREAD BOX AND SUPPORT. APPLICATION FILED APR. 26, 1909.

Patented Sept. 27, 1910.

WITNESSES.

tlNiiED %TATE$ FATENT OFFICE.

GEORGE w. NIXON,

OF CHATTANOOGA TENNESSEE, ASSIGNOR T0 NIXON MINING DRILL 00., INCORPORATED, OF CHATTANOOGA, TENNESSEE.

MINING-DRILL THREAD-BOX AND SUPPORT.

To all whom it may concern:

lie it known that I, Gnonon siding at Chattanooga, in the county 0 Hamilton and State of Tennessee, have invented certain new and useful Improvements in Mining-Drill Thread-Boxes and Supports, of which the following is a specification.

In coal mining, and other mining, it is a fact that the available room or space within a mining chamber is limited. In constructing drills for use in mining it is desirable to have adrill which will operate not only in an open space but also in a confined space in such manner that the longest possible feed may be obtained from the drill without resetting the support. I therefore have designed an improved construction of thread box wherein the pivot studs or trunnions are located at one extreme end of the thread box and cooperate with a support wherein the trunnion bearings are located at one side of the central axis of the support so that four distinct positions of the thread box may be obtained to give the feeding adjustments of the drill four distinct advances so that in the commencement of the cut the feed box may be at the extreme distance from the hole and may be four times adjusted closer to the hole, thereby enabling a deeper cut to be made with one location of the support or post, and thus avoid the necessity of changing the location of the post after the thread bar has reached the limit of its movement in the thread box as is the case where the thread box is centrally pivoted in central bearings of a support.

In its more subordinate nature the invention also includes those novel details of construction, combination and arrangement of parts, all of which will be first described in detail and then be specifically pointed out in the appended claims, reference being had to the accompanying drawings, in which:

Figure 1, is a side elevation illustrating the application of my invention, with the feed box located in the position farthest from the hole. Fig. 2, is a similar view showing the feed box located closer to the hole in its second position. Fig. 3, illustrates the third position of the feed box and post. Fig. 4, designates the fourth position thereof. Fig. 5, is a side elevation illustrating a modified form of support or post in connection with which my feed box may be W. Nixon, re-

Specification of Letters Patent.

Application filed April 26, 1909.

Patented Sept. 27, 1910.

Serial No. 492,246.

used. Fig. 6, is a cross section of the screw the thread box being open. Fig. 7, is a similar view of the thread box closed.

Referring now to the accompanying drawings in which like letters and numerals of reference indicate like parts in all of the figures 1 designates the screw bar of a mining drill, which may be of any approved type, such for instance as that disclosed in my co-pending application filed on even date herewith, Serial No. 492,245.

2 represents the thread box which is made in halves hinged together as at 2 and provided with apertured ears 2 to receive the key pin 2 that is retained by a chain 2 secured to the pin and to the thread box section. The thread box is provided with trunnions 2 located at one extreme end of the thread box to cooperate with the trunnion bearings 3 of a post clip 3 that is securable to a post t by a set screw 3 or secured in any approved manner. The post 4 is centrally slotted at l and provided with the usual spike a and screw bar 4 by means of which the post may be set up to have pivotal movement on its longitudinal axis.

In the modified form shown in Fig. 5, I dispense with the clip 3 and in lieu thereof the postis notched as at t to receive the trunnions 2 the notch being undercut as at 4; so that the thread box may be used with the thrust in the direction of either of the arrows in Fig. 5.

Assume now that the drill is set up as shown in Fig. 1, with the thread box 2 farthest from the hole, as soon as the operator has drilled the full length of the screw bar 1 the thread box 2 may be turned 180 degrees on its trunnions 2 to the position shown in Fig. 2 when an additional length of feed equal approximately to the length of the screw box may be obtained without changing the position of the box. Now by turning the post 180 degrees with the screw box in the position shown in Fig. 2, the adjustment shown in Fig. 3 18 obtained adding thereby an additional amount of feed to the thread bar equal to the length of the pro jecting portion of the thread box that projects beyond the front face of the support 4, and by turning the thread box 2 on its trunnions 2 180 degrees from the position shown in Fig. 3 to that shown in Fig. 4t an additional feed equal approximately to thelength of the thread box may be again obtalned,

thus the total additional feed obtained by my construction of thread box and post from i the position shown in Fig. 1 to the posi- I tion shown in Fig. 4 will be more than three times the length of the thread box. The same adjustments may be obtained with the post shown in Fig. 5.

From the foregoing description taken in connection with the accompanying drawing it is thought the complete construction, operation and numerous advantages of my invention will be readily understood by those skilled in the art to which it appertains.

hat I claim is:

1. In combination with a screw bar of a drill,ofa thread box having trunnions at one end, a slotted support having closed trunion bearings to receive said trunnion and permit rotation of the thread box on us trunnion axis through an arc of 360 and to permit said thread box to be used in any position.

2. In combination with a screw bar of a drill, of a thread box having trunnions at one end, a slotted support having trunnion bearings to receive said trunnions and permit 1 rotation of said thread box through an arc of 360, the greatest width of said thread box exclusive of said trunnions being less than the width of the slot in said slotted support to permit said thread box to be swung through said slotted support, substantially as shown and for the purposes described.

3. In combination with a longitudinally slotted support, a clip embracing said support and secured thereto, said clip having a pair of closed trunnion bearings at one side of the support, a thread box having trunnions at one end mounted in said trunnion bearings, said thread box exclusive of said trunnions having its greatest width less than the width of the slot of said support, in virtue of which said thread box may be swung on its trunnions through an arc of 360, and means for rotatably mounting said longitudinally slotted support.

GEORGE NIXON.

lVitnesses XV. POLLARD, lV. A. KELLY. 

